Fla. researchers tracking great white sharks

This photo taken Jan. 8, 2014, shows Jim Gelsleichter, an assistant professor in the biology department at the University of North Florida holding one of the receivers which will be used to track shark movements in Jacksonville, Fla. (AP Photo/Florida Times-Union, Bruce Lipsky

MATT SOERGEL, The Florida Times-Union

Published: Sunday, January 19, 2014 at 6:25 a.m.

Last Modified: Sunday, January 19, 2014 at 6:25 a.m.

JACKSONVILLE - The search for great white sharks off the coast of Jacksonville — just off the beach, in fact — is about to get a lot more serious.

By the end of this month, the University of North Florida's shark-research program expects to place as many as 10 sensors in the Atlantic. If a great white that's been tagged by a tracking device swims within a few hundred yards of a sensor, scientists will know.

The devices will be near the beach, perhaps a half-mile or mile from the sand. The great whites, after all, do come in close.

The nonprofit shark research group, Ocearch, last January tracked a 16 1/2-foot great white named Mary Lee in the surf zone in Jacksonville Beach.

They then brought their research vessel on an expedition to Jacksonville and caught and tagged 14-foot Lydia within eyesight of Hanna Park. Meanwhile, the satellite tag on Katharine was showing that shark hanging around near Cape Canaveral.

The Ocearch sharks are tracked by GPS devices, which are caught by satellite every time they rise to the surface.

Don't think of UNF's nearshore devices as early-warning signals, though. The sensors store information but can't transmit it instantly; it will have to wait until researchers travel to them and download the data.

Jim Gelsleichter, a shark expert at UNF, is still making final plans on where to place his school's sensors, which will be able to spot the sharks underwater.

He said they'll most likely be attached to buoys in Nassau Sound, Fort George Inlet, the Mayport area, Jacksonville Beach, Ponte Vedra Beach and St. Augustine.

Chris Fischer, founder of Ocearch, is on an expedition in the Galapagos Islands. He said he was "thrilled" by the new sensors off Jacksonville, calling them a crucial link in researchers' understanding of great whites.

Placing the sensors close to shore is a big plus, too, Fischer said. The tracking devices are showing that some great whites spend much more of their time poking their noses into inlets and cruising along beaches than what was once believed.

"What's really surprised us is the coastal portion of their life, which particularly seems significant in the Southeast," he said.

Ocearch's high-profile spottings of great whites in the area created a buzz in traditional media outlets and social-media sites. Mary Lee, a celebrity shark, even has a Facebook page.

So are there more great whites in the ocean off Jacksonville?

Experts aren't sure. "Finding white sharks is tough," said Greg Skomal, a shark expert at the Massachusetts Division of Marine Fisheries who accompanies the Ocearch vessel on its expedition to Jacksonville. "Counting them is even tougher."

But Skomal said there has definitely been a big rebound in the great-white population off Cape Cod the last couple of decades. That's due to efforts to protect the seals there, which sharks find tasty.

Thanks to tracking devices implanted in those Cape Cod sharks, scientists know they frequently range as far south as Florida. So it seems likely that more Cape Cod sharks equals more Florida sharks.

"I don't think it's any reason to run up and down the beach screaming," Gelsleichter said. "But the scientist in me is curious about it."

Gelsleichter, an assistant professor of biology, has been fascinated by sharks ever since he saw "Jaws" at age 6. Yes, he knows it wasn't an age-appropriate movie, but there you have it.

He's now directing the university's Shark Biology Program, which studies the many species of sharks in the area. Great whites, the apex predator of the ocean, attract the most media attention, however — even if they're not much of a threat to humans on the East Coast.

In July 2012 a swimmer was bitten off Cape Cod and survived; that was the first great-white-shark injury there in 75 years, Gelsleichter said.

Meanwhile, the International Shark Attack File at the Florida Museum of Natural History said there has not been a single documented instance in Florida's recorded history of a great white attacking a human.

Scientists once thought the animals summered off Cape Cod and wintered in the Southeast — a pretty simple pattern.

But it looks now that they're off the Southeast coast, some of them anyway, even during warmer months. "We're seeing good evidence to show that the animals are not just winter residents," Gelsleichter said.

UNF's devices will be able to pick up any of the Ocearch-tagged sharks, along with about 20 others tagged by harpooners off Cape Cod.

Each shark emits a distinct signal, so scientists will be able to identify and track each one.

UNF already has three devices working, but they're at popular diving spots far offshore. They picked up the presence of two great whites last winter.

The Ocean Tracking Network of Canada provided some of the funding, and a UNF grant kicked in $4,000.

The UNF sensors will tie in with a network of such devices to the north and south, filling a crucial gap in knowledge, Gelsleichter said.

Much remains to be learned about the travel patterns and life cycles of the great white.

"I think definitely that we're an important part of the puzzle," he said.

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